1. Field of the Invention
The present invention relates to an electrophotographic reproducing apparatus in which an optical scanning unit assembled in advance and a reproducing apparatus body unit including an electrostatic latent image receptor such as a photosensitive member and assembled in advance independently of the optical scanning unit are jointed into a unitary structure.
2. Description of the Prior Art
The electrophotographic reproducing apparatus is classified in accordance with an exposure system for exposing a document to be reproduced, into the type, in which a document glass plate is moved, and the type in which an optical scanning system is moved. According to the prior art, in case the electrophotographic reproducing apparatus of the optical scanning system moving type is to be assembled, the reproducing apparatus body is first framed. To this frame, there are consecutively attached stationary systems such as a photosensitive drum, a developing device and fixing device. On the reproducing apparatus body thus assembled, there is reciprocally movably placed an optical scanning unit which includes a document illumination lamp, lenses, mirrors and so on. Since the driving power of the optical scanning unit is usually supplied from the drive source for the photosensitive drum and a paper feed mechanism, a power transmission wire is made to run in operational relationship with the stationary systems after the optical scanning unit has been arranged. In this meanwhile the spacings between the mirrors and the lenses and between the mirrors are so adjusted that the light reflected from the document may be focused upon the photosensitive drum, and the lens positions are adjusted while taking the magnification or contraction of the image into consideration. The assembling and adjusting procedures thus far described invite many troubles and take much time. As a matter of fact, the adjusting procedures of the optical scanning unit accounts for a large percentage of the assembling procedures.
In order to reduce the number of the assembling steps to some extend, therefore, there has been conceived a method by which an optical scanning unit having its mirror running mechanism and its parallelism adjusted in advance is assembled with the reproducing apparatus body having its stationary systems assembled. According to this method, nevertheless, it is still necessary to make the driving wire run on the stationary systems after the assembly, to determine the spacings between the mirrors while observing the focused level of the image, and to determine the positions of the lenses while inspecting the magnifications. Thus, the adjusting work taking the most time is little lightened.